ZnO/Zeolite composite photocatalyst for dyes degradation

Abstract

The ZnO/Zeolite composite was obtained by the method of deposition of zinc oxide on the surface of hydrogen form of the faujasite-type Zeolite Y that was impregnated with a hydrolysis product of zinc acetate precursor and calcinated at 300 °C for this. The deposition of zinc oxide covering the nanoparticles of the initial Zeolite was confirmed by SEM. The zinc oxide phase of the hexagonal syngony of the wurtzite type with a content of 20 wt. % in the synthesized ZnO/Zeolite composite was proved by XRD and XRF. The BET surface, the total, and the micropore volume of the initial Zeolite decreased, and the average pore size rose as a result of ZnO deposition. The centers with pKa = 9.45 which were OH⁻ groups attached to the edge regions of the surface doubled after zinc oxide deposition on the Zeolite since ZnO nanoparticles tended to interact with the water molecule. That was the very reason for the advanced photocatalytic activity of ZnO/Zeolite composite toward the anionic dye. Congo red dye (8.0, 25.0, and 50.0 mg/L) was decolorized completely for only 1 min, but methylene blue dye (8.0 mg/L) decomposed incompletely even after 1 h of UV irradiation.